Semi closed reef system

[Mouse]

I have just been thinking about the theory behind developing a semi closed reef system.

The basic difference in a system of this type would be the fact that the RO/DI unit would be running constantly, with the salinity kept in check by using a conductivity meter and a heavily salinated reservoir.

As the RODI unit would be running constantly you would need the unit plumbed into a drain of some sort. You could then have a surface skimmer that connected directly to the drain, so that the water on the surface would effectively be removed alltogether. And as i beleave that the majority of Protiens and polutants collect in this regeon it would be the best place to remove it.

Then to ensure a constant salinity, you would need some kind of reservoir with a massively high salt concentration to correct it. This would be managed with a conductivity meter and a small powerhead to supply the aquaria with ready mixed salt.

Say you have a 35G per day RODI, you would effectively be making a waterchange of 35G every day. This may eliminate the need for a protien skimmer, and may even reduce heat build up sufficintly to do away with a chiller.

What do you think, has it been done before? Would this cause big problems with calcium levels etc?

Only problem would be when the water bill came, but if this really worked who cares.

 

[Chucker]

Say you have a 35G per day RODI, you would effectively be making a waterchange of 35G every day. This may eliminate the need for a protien skimmer, and may even reduce heat build up sufficintly to do away with a chiller.

Actaully, you would not have a 35g water change daily. Since there is constant turnover of water, there is no starting and stopping point for a change. If you are surface skimming straight to a drain, you will be losing both "old" and "new" water at the same time.

This is one of the reasons why a system that has defined water changes will be more effective in removing wastes. The only systems that can really be effective with this methodology are flow-through systems using ocean water. In that case, any waste created by the tank is effective removed simply by the huge dilution factor by constant flow.

The most important issue with a system like this IMHO is that it heavily relies on sensing devices to remain in balance. If the RO, salinity meter, surface skimmer, valves on the reservoir, or any other key device goes haywire, the system could be in instant jeopardy.

 

[Anonymous]

hi.
I have seem this constant water change issue come up many times both on this board, and elsewhere.

I agree with Chuck. If you do a constant water change of 35 gal on a 35 gal tank, it probably equivalent to do a 10% weekly water change. The formular is something like this: limit n->infinity, c->0 (v/(v-c))^n

It is a real waste of salt and water, unless you can get them for free, like having clean ocean water right next to your house or something.

But if you really want to persude this idea, think of a way to drain 30 gal of water out of the tank, then add 30 gal of newly mixed saltwater to it in very short time. Then you can truly get away with protein skimmer and chemical-related equipement.

 

[DBW]

Major thing you have to factor in, what happens if the high salinity reservor/doser fails? You will either end up with a freshwater tank or a salt pan lake. You need to have some procedures or equipment in place so that this does not, and cannot, happen.

 

[danmhippo]

In places I live, I can't afford to throw away 35G of water a day. If we are just talking about $$ involved, you need to set aside $$ for daily water waste, RO discharge, RODI membrane due to accelerated usage, Ca and akalinity resupplementation, electricity, monitoring devices, sensors. The only thing you are saving is the cost of the protein skimmer.

IMHO, not worth the trouble.

 

[2poor2reef]

You could do it in multiple stages. Have the ro/di output to a seperate container with a powerhead and something to add salt i9nto that container. Only make that resevior available to the reef tank when salinity/temp is right.

You might be able to work something out where the change water is slightly cooler than the existing water at the surface of the tank. That way the newer water would tend to sink and more of it would effect the change and not be siphoned off. In that scenario, you would not change continuously, but maybe several times per day on a timer.

Just thinking. Make any sense?